The object of this project is the elucidation of the biochemical correlates of compensatory skeletal muscle hypertrophy. These studies will give greater insight into the physiological chemistry of normal and pathologic skeletal muscle, and into how the weight of a tissue is increased with stimulation. Present topics of investigation include: 1) The relationship between skeletal muscle and connective tissue in hypertrophy; 2) myofibrillar protein synthesis and degradation in hypertrophy; 3) the relationship between compensatory skeletal muscle hypertrophy and endurance training; and 4) localization of phosphoinositide changes in hypertrophy using radioautography.